Solutions and films of glycated chitosan

Abstract

Preparations containing glycated chitosan in a physiologically compatible carrier are described. Viscoelastic preparations comprise 1.0-12.0 percent by weight of glycated chitosan in an aqueous solution while lower viscosity solutions possess 0.1-0.5 percent by weight glycated chitosan. The otherwise free amino groups of the chitosan polymer are preferably 30-90% glycated and possess an average molecular weight of between 100,000 and 2,000,000 Daltons, and, most preferably between 100,000 and 1,000,000 Daltons.

1 - 14 . (canceled)  
     
     
         15 . An eye drop preparation comprising less than 1 percent by weight of a glycated chitosan polymer dispersed in an aqueous solution, said aqueous solution having a viscosity of between 10-100 centistokes measured at 25° C.  
     
     
         16 . A dried film comprising glycated chitosan.  
     
     
         17 . A medicament for providing the sustained release of a therapeutic substance, comprising glycated chitosan having entrapped therein a desired amount of said therapeutic substance.  
     
     
         18 . A method of preparing ophthalmic wetting agents for topical application to an eye comprising the steps of: 
 preparing an aqueous solution having less than 1.0 percent by weight of glycated chitosan and 30% to 90% glycation of otherwise free amino groups of said glycated chitosan;    wherein said aqueous solution has a viscosity from about 10 centistokes to approximately 100 centistokes.    
     
     
         19 . A method of preparing ophthalmic wetting agents according to  claim 18  wherein said aqueous solution comprises 0.01% to 0.5% by weight of glycated chitosan.  
     
     
         20 . A method of preparing sustained release ophthalmic wetting agents according to  claim 18  wherein said aqueous solution comprises 60% glycation of otherwise free amino groups of said glycated chitosan.  
     
     
         21 . A method of preparing sustained release ophthalmic wetting agents for topical application to an eye according to  claim 18  further comprising the steps of: 
 applying said preparation to an eye;    allowing enzymes in eye secretions to break down said aqueous solution for providing characteristics of sustained release.